1. Field
The disclosed embodiments relate to image production and, more particularly, to a system and method for processing printed media.
2. Brief Description of Related Developments
In high speed continuous feed printing, one or more printing engines may be coupled directly to a number of post processors to perform operations after printing. These types of systems may be referred to as online post processing systems. In some cases, the actual post processing throughput may be limited by the printing operations throughput. In others, the post processing operations themselves may limit throughput because they may not be capable of processing printed media as fast as produced by the printing engines.
For high volume printing production, it may be cost efficient to de-couple printing operations from post processing operations. For example, printed media comprising individual pages or groups of pages referred to as jobs may be formed into a roll and transported to a separate station or area for post processing operations. At the post processing station each job is identified in order to perform operations such as cutting, slitting, stacking, folding, inserting into envelopes, weighing and stamping. This type of operation may be referred to as offline post processing. Offline post processing may allow for load balancing among a number of printing operations and among a number of post processing operations.
The actual post processing operations to be performed may be printed directly onto the printed media, for example, in the margin as a bar code, or other small marks on the media, that are read by the various off line post processing equipment as the media passes through the equipment. The operations may be in the form of information, commands, or messages, generally referred to as instructions. Some exemplary instructions may include:                The page has been printed and must be processed; or the page has been ejected and should be discarded        The page is part of a set and a given post processor action is to be performed when the set is complete. For example, “This is a mail message of three pages for John Doe, the next set is a mail message of two pages for Bill Smith; each is to be stapled, folded and inserted into different envelopes”.        The page was subject to a jam and the post-processor should stop when reaching it, and call for operator attention.        The page length changes hereafter and the post-processor should (for example) adjust a cutting distance.        The pages are provided solely for post-processor alignment and adjustment. They require: stop; call for operator attention and action, and they should be discarded afterwards.        Where the post-processor is a folding machine used to fold booklets that are trimmed and sewn, commands may include the description of the folding pattern (the imposition pattern) and the direction of the page.        
Other instructions may include a paper advance clock or a page break signal.
It would be advantageous to provide post processing instructions without marking the media.